An electric power converter is an apparatus which converts electric power from one form into another form. Classes of electric power converters include AC-to-DC converters, AC-to-AC converters, DC-to-AC converters, and DC-to-DC converters.
DC-to-DC power converters are utilized in many applications to regulate an input source having a variable DC voltage level to produce an output at a predetermined DC voltage level. DC-to-DC power converters can be simultaneously utilized to step-up or step-down the voltage level of the input source, i.e. to produce an output DC voltage level which is greater or less than or equal to the input DC voltage level. In some satellite and spacecraft applications, for example, a DC-to-DC power converter is utilized to step-down a bus voltage which varies between 51.55 VDC to 51.35 VDC to produce a constant 65 VDC signal.
For these applications, the DC-to-DC power converter can include a linear regulator having an output set close to the minimum bus voltage, e.g. 51.35 V, to minimize power loss. However, for high bus voltages, the power loss in the regulator is high and hence the overall efficiency is decreased. In order to maintain efficiency at various bus voltages, the DC-to-DC power converter can comprise a switching regulator. However, switching regulators are typically not as efficient as linear regulators for low bus voltages.